1. Field of the Invention
The present invention relates to a liquid electrophotographic image-forming apparatus, and more particularly, to a liquid electrophotographic apparatus including an anti-wraparound device for preventing developer removed from a transfer belt from flowing toward the sides of a cleaning blade and contaminating a main body of the apparatus.
2. Description of the Related Art
Generally, a liquid electrophotographic image-forming apparatus is an apparatus producing an image by charging a surface of an exposure medium using a charging device, forming an electrostatic latent image by exposing the exposure medium to light irradiated from a laser scanning unit according to a printing signal, and thereafter forming and transferring the image onto a printing medium using a transfer belt.
The liquid electrophotographic image-forming apparatus typically uses a contact charging method by which a predetermined electric potential is formed on the surface of the exposure medium through contact between the charging device and the exposure medium. A difference in electrical potentials created by the charging device is then used to attach the developer to the electrostatic latent image formed on the exposure medium, transfer the image from the exposure medium to the transfer belt, or transfer the image from the transfer belt to the printing medium.
However, the image may not be totally transferred from the exposure medium to the transfer belt, or from the transfer belt to the printing medium in all cases. When this occurs, a part of the image may remain on the exposure medium or on the transfer belt. Developer that remains on the transfer belt can then overlap with another image to be formed, thereby making it impossible to obtain a complete image. Therefore, a device is required to remove the remaining developer from the transfer belt. Several such devices for removing remaining developer from the transfer belt are disclosed in U.S. Pat. No. 5,873,016, U.S. Pat. No. 5,017,969, and Japanese Laid-open Patent No. 13-183951, the entire content of each is incorporated herein by reference.
The devices disclosed in the above patents use a cleaning blade to clean a transfer belt and remove remaining developer therefrom. The developer removed by the cleaning blade is stored in a container placed along the cleaning blade. However, since the removed developer has a high concentration, in some cases 20% to 30%, some of the developer flows toward the sides of the cleaning blade, thus contaminating the transfer belt. This phenomenon is referred to as a wraparound phenomenon. Consequently, the following image to be printed may be dragged by the transfer belt due to the excessive developer in a next transfer process.
Accordingly, a need exists for a device for preventing the developer removed by the cleaning blade from flowing toward the sides of the cleaning blade and contaminating the apparatus.